Slug feed device



Dec. i5, 1953 P. INGRAM 2,662,760

SLUG FEED DEVICE Filed Aug. 27, 1949 2 SheetS-Sheet l Pafzg @farm 55 RgmyME/LLHE Dec. l5, 1953 P. INGRAM SLUG FEED DEVICE 2 Sheets-Sheet 2Filed Aug. 27, 1949 Patented Dec. 15, 1953 rSLUG FEED DEVICE PaulIngram, Cleveland, Ohio, assigner to Thompson Products, Inc., Cleveland,Ohio v@punition August 27, 1949, Serin No. 112,771

(o1. zee e) '6 Claims. 1

This invention relates .to a device `for moving slugs of meta-lsuccessively toa processing station. More particularly the inventiondeals with a `device Vfor feeding slugs vof metal .through an .nductionheating unit and for metering heated slugs to a press loading positionat the discharge end of the heating unit.

In the die forging or extrusion of metal it is desirable .to heat themetal piece to a relative high temperature just prior to loading themetal into the press. The metal should not be allowed to cool off toomuch at the loading ,station and, therefore, it is desirable that theAmetal slugs be delivered to the hand loading station .at approximately`the same rate as they yare being loaded.

According to `the teaching vof the present invention, slugs of metal are.fed in a gravity ramp that yhas `a V-shaped lower yopen `end locatedVbetween and in axial alignment with .a tubular passage through theheating unit and with a powerdriven lrecproeating push rod. As each slugmoves into the V-shaped end, the push rod oontacts it and forces itlinto the passage through the heating unit. As one slug enters thepassage, a previous slug is pushed out `at the other end into ka chutewhich is directed to the loading station of the press. To regulate therate of delivery of the slugs to the loading station of the press, thereciprocating push rod is driven through a variable speed transmissionso that the speed of operation can be easily Controlled. The heatingunit employed has, of course, the necessary heating capacity to heat theslugs to the desired temperature. A safety switch mechanism, which istripped to die-energize the heating coils and stop the Ymovement of thepush rod, is located .the inclined ramp. When the ramp is erupts',y thesafety switch is tripped for preventing :the over-heating of slugs thatare already in the heating unit.

A second safety device is provided in the form of a metering platedisposed in front of the entrance of the `furnace so that no oversizeslugs of metal will pass into the furnace. When an oversize slug isstopped by this safety plate, a switch in the drive mechanism of thepush rod is tripped to cie-energize the power drive means.

It is, therefore, an important object of the present invention toprovide a slug feed mechanism that may be readily adjusted for varyingthe rate of delivery of slugs through a heating unit.

Another object of this invention is the provision of a slug feedmechanism having a safety control for cle-.energizing the `heating coilswhen the feeding ramp is empty.

A still further feature of this invention is the provision of means forpreventing oversize slugs of metal from entering the heating unit andinterconnected safety trip means for cie-energizing the power Ameansthat pushes the slugs through the furnace.

Another object of this invention is to provide a slug feed device havingreadily removable parts, permitting substitution of parts to accommodatevarying sizes of slugs.

While the slug feed .device of this invention is particularly useful forfeeding metal slugs through an induction heating furnace for subsequentdelivery to the loading position of a press, it is to Abe understoodthat the invention is not to be limited to this installation since ithas general application wherever articles are to be successively fed toan operating station.

Other and further features, objects and advantages of the presentinvention will become apparent to one skilled in the art from thefollowing detailed description talren in connection with theaccompanying drawings.

On the drawings:

Figure 1 is a top plan view of the slug feed device of the presentinvention;

Figure 2 is a fragmentary side elevational view of the slug feed deviceof Figure 1;

Figure 3 is a fragmentary plan view of a portion of the mechanism ofFigure 2 taken on line III- III of Figure 2;

Figure 4 is a fragmentary vertical sectional view taken on line IV-IV ofFigure 2;

Figure 5 is a sectional view taken on line V-V of Figure 2;

Figure 6 is an enlarged fragmentary elevational view of a portion of themechanism of Figure 1 'taken on line VI-VI of Figure 1;

Figure '7 is an enlarged fragmentary plan view of a portion of thedevice of Figure 2 taken on line VII-VII of Figure 2;

Figure Sis a fragmentary vertical sectional view taken on line VIII-VIIIof Figure 1; and

Figure 9 is a detail view of a metering plate on a reduced scale.

As shown on the drawings:

In Figures 1, 2 and 3, the reference numeral I0 indicates generally aframe support structure having spaced pairs of upright leg members Il,l2 and 13 secured, as by welding, at their lower end to longitudinalangle members I4 at each side of the structure. At their upper end, thelegs H and l2 are connected by longitudinal straps l5 which are in turnsecured together by cross vstraps i6 to define an upper supportplatform. At the upper end of the leg I3, longitudinal angle members ilrigidly connect the leg if; to the leg i2 while spaced flat bars i8 aresecured transversely of the structure to define a lower platform.

An induction heating unit 2d is suitably secured in a cradle El formedby three angle memn bers Ela, 2lb and 2te that are welded together. Theunit E@ is supported on the lower platform on a pair of spaced crossstraps 23 which are welded to the underside of the members Zia and Zicas shown in Figures 2 and 3. The straps 23 are slidably supported on thedat bars I8 which are located directly below. The ends of the crossstraps 23 are provided with slots 25, Figure 3, through which adjustingscrews 26 pass for threaded engagement in pads 2'! secured to the undersurface of the side longitudinal angle members l?. These slots permittransverse adjustment of the heating unit relative to the supportstructure when it is necessary to remove slugs from the furnace, or toreplace a part of the heating unit.

The heating unit 2t comprises a housing 3S across the upper part ofwhich is secured a ceramic tube Si denning a passage 32 through 'whichthe metai slugs move. The upper part of the housing is preferably lledwith plaster or the like around the tube 3l. An induction heating coil33 is wrapped around the tube 3l and is connected in a circuit with acapacitor 3s to a terminal box 35 secured to the side of the housingCooling liquid is supplied to the coil by conduits 36 and 3l.

A tubular discharge chute Se is suitably sup ported adjacent the housingBt at the end of the passage 32. Thus, metal slugs leaving the passageare deposited in the chute and directed to the loading platform of theextrusion press. If the press is shut down for adjustment the slugs maybe delivered through an opening lll in the chute ed which is normallyclosed by a pivotal gate 52 hingedly mounted on the chute de and havinga handle d3 for easy manipulation. This by-pass is necessary so that theheating unit can be kept in operation during minor adjustment of thepress so that no unnecessary delay will be incurred in reheating thecold slugs.

Metal slugs are directed to the entrant end of the passage 32 by meansof a gravity feed ramp d5 that is inclined upwardly to the left as seenfrom the drive end of the machine in Figure 4. The ramp has a base it?,Figures 1 and 2, and an upstanding side wall #i8 secured to the base. Asecond upstanding side wall #te is slidably adjustable on the base t?toward and away from the wall #it by means of adjusting screws 56disposed in a slot 5i in the base il?.

The ramp d5 has a V-shaped lower end portion es, Figure e, that holdsthe slug in alignment with the passage 32 as the slug is pushedthereinto. An adjustable stop 54 is mounted on top of the outer slopingside of the V end 53 to prevent the slugs from advancing up this side.The stop can be adjusted toward and away from the bottom of the V toaccommodate slugs of different diameter and hold them in alignment withthe passage 32.

The ramp t5 has a web portion 55, Figure 4, extending down from itsbottom wall. This web is secured b-y bolts 5i'V to a guide housing 58that has a base 5ta extending transversely of the support structure andsecured at its ends in the side longitudinal support straps l5. 57passes through aligned vertical slots 50 in the housing 5t permittingthe ramp 45 to be pivotally adjusted about the other bolt as an axis toac:1 curately align the bottom of the ii-shaped end with the entranceopening of the passage 32.

A cover 6G is adjustably secured on the ramp i5 in brackets Si. A doorS3 is slidably disposed at the lower end of the cover 2li to facilitateremoval of slugs which may cause a jam at the entrance of the passage32.

The slugs are forced through the passage 32 by means of a push rod 65that is slidably journaled in a longitudinal passage 6@ in the guidehousing 58 and is pivotally connected to a connecting rod Si. Theconnecting rod t? is eccentrically connected to a rotating disc 63 thatis driven from a source of power through a variable speed transmissionOne of the bolts The entire variable speed transmission I0 and the driveconnection thereto are mounted on a plate 12, Figure 2, that is slidablelongitudinally of the support structure in ways defined by the supportstructure and straps 'i3 suitably secured and spaced above the supportstructure. Ear members 'l5 depending from the bottom of the plate 'I2have aligned threaded openings which receive a feed screw'lt which isjournaled for rotation in a transverse structural frame member 11. Aspacer sleeve 18 is disposed around the screw 'IB between the structuralmember 77 and a shoulder 'is on the screw 76. As the screw is rotated inone direction by the hand wheel 8i! attached thereto, the plate is movedlongitudinally away from the guide housing 58. It will, of course, berecognized that for any given length of slug the movement of theconnecting rod 51 must be such that the slug in the heating coil will bestopped just short of the exit of the passage 32. In the intermittentmovement through the induction heating coil it is desirable that theslug be stopped inside of the coil just short of the exit of the passage32 so that it will not cool oi prior to being directed to the loadingstation of the press. Thus, it is necessary that the throw of the pushrod 55 be adjustable for various sizes of slugs to get this desiredeffect. In the present invention this is accomplished by means of theslidable table mounting for the drive mechanism.

In order that the ceramic tube Si defining the passage 32 be protectedfrom damage due to oversize slugs, there is provided a safety plate 82which is mounted by means of brackets 83 and 84 from the web portion 55of the ramp i5 by means of bolts S5, as seen in Figures l and 2. Thebrackets 83 and 8d have hooked end portions 83a and 84a which extendaround behindl the safety plate to hold it rmly against the lower end ofthe ramp e5. The safety plate has an opening 82a, Figure 9, which ispositioned directly in line with the V-shaped lower end 53 of the ramp45 and with the passage 32. The opening 82a in the safety plate is of apredetermined diameter and it will accommodate only slugs of a certainsize. Thus, for any size of slug the safety plate must be chosenaccordingly. When an oversize slug is pushed forwardly by the push rod65 it will abut the safety plate and will prevent the forward movementof the push rod 65.

In order to prevent any jamming or breaking apart there is provided aspring-urged safety pin 81, Figure '7, which is disposed in a hubportion 88 keyed to a shaft 39 extending from the variable speedtransmission 'HL Thus, during normal operation, the disc 58 is driven bythe hub 38 through the spring-urged. pin 81. This pin is adjustably heldin thehub 38 by means of a threaded collar 9i. The lower end of the pin8l has a conical shape which extends into an opening 92 in the disc 68for driving engagement therewith. When the forward movement of the pushrod E5 and the connecting rod 67 is stopped due to the abutting of anoversize slug against the safety plate, the conical end portion of thepin S1 will ride out of the opening 92 and permit free rotation of thehub 88 relative to the disc 63. When the pin 81 is moved upwardly todotted line position indicated in Figure 7, further rotation` of the hub38 will cause the raised pin Si to contact a roller 94, Figure 6, whichis mounted at the end of a bell crank 95 which has one end portion 95a,in contact with the tripping element Sii of the switch 91. Thus, as theextended end of the pin al rotates with the freely rotating hub 88 itcontacts the roller 94 and trips the switch to shut oif power to thevariable speed transmission. Thus, there is provided in this invention asafety means for shutting down the power-drive mechanism when anoversize slug contacts the safety plate.

Since each metal slug is moved through the heating passage t2 of theinduction coil by the contact of a following slug, there is always atleast one slug in the passage being heated. lf the supply o slugs in thel5 were to stop, the feeding of the slugs through the machine would stopin spite of the continued movement of the push rod 65. Therefore, thereis provided in this invention an automatic trip means actuated by theweight of the slugs in the ramp to shut olf the power to the drivemechanism and to cle-energize the heating coil when the ramp d5 becomesemptj. This mechanism is shown in Figures e and 8 and comprises a lever39 pivotally mounted by a pin lili? from an ear member l il! of the rample having one end 99e', arranged to contact the plunger itil of anelectric switch 84. The lever 5t in normal operation extends upwardlythrough a slot ltli, Figures l and 8. The weight of the slugs passingover this lever will cause it to pivot downwardly and push the push rodI e3 to energize the circuit to the heating coil A and the power drivemechanism of the variable speed transmission. When the ramp becomesempty and the last slug is deposited in the V- shaped end 53 the lever83 will pivot upwardly permitting the spring-urged plunger |93 to moveout of the switch itil and Lie-energize the circuit to the heating coiland the power-drive means. Thus, this safety trip mechanism provides anautomatic means for shutting off the power to the heating element andpreventing melting of the slugs in the heating passage when they aretemporarily detained therein.

From the foregoing description it will be seen that there is provided inthis invention a very simple slug feeding device the rate of speed ofwhich can be quickly varied to provide the exact rate of discharge ofslugs from the heating unit that is required at the press. Further,there is provided in this invention automatic safety means for shuttingdown the power-drive means when an oversize slug is fed to the mechanismand also safety means for rie-energizing the power-drive means and theheating element when the supply of slugs is stopped. This mechanism isalso adjustable to provide a variable stroke mechanism so that the endof the stroke is correlated with the end of the heating passage so thatthe slug will always remain inside the passage during the interval justbefore it is discharged therefrom. Thus, no cooling of the slug in thepassage will be effected. Another feature of this invention is theny-pass means in the discharge which per mits the feeding mechanism tocontinue its op* eration even though the press is temporarily shut downthus obviating the re-heating of the cooled slugs in the heating coil.

It will be understood that modifications and variations may be effected'without departing from the scope of the novel concepts of the presentinvention.

I claim as my invention:

l. A device for feeding slugs comprising a heating unit having apassageway for eating slugs therein, means for successively aligningslugs with said passageway, power means for pushing aligned slugsthrough said passageway, a metering plate having a slug receivingaperture smaller than the cross sectional area of the passagewayadjacent the receiving end of said passageway preventing movement ofoversize slugs thereinto, and a load responsive mechanism to stop saidpower means whenever said aperture does not freely receive a slug pushedby said power means.

2. A device for feeding slugs comprising a heating unit having apassageway therethrough, a push rod arranged to move slugs through saidpassageway, a rotatable disc pivotally holding one end of said push rod,a power driven disc rotatable on the same axis as said rotatable disc,each of said discs having an aperture therethrough, a spring-urged pinslidably disposed in the aperture in the power driven disc and having aconical point disposed in the aperture in the rotatable disc connectingthe discs in driving relation, a switch adjacent said power driven discfor controlling the power thereto, and a metering plate adjacent thepassageway to said heating unit preventing movement of oversize slugsthereinto, said spring urged pin being movable out of the passage insaid rotating disc when an oversize slug is stopped by said meteringplate and movable against said switch to deenergize said power drivendisc.

3. A device for feeding slugs to a heating unit having a passagewaycomprising a metering plate having a sized orifice therethrough, saidpassageway being of larger cross sectional area and adjacent said plate,means for automatically delivering slugs to a position in front of saidmetering plate, a reciprocating pusher adapted to successively pushslugs through the sized orifice in said metering plate into saidpassageway, power means for driving said reciprocating pusher, means formechanically disengaging said power means from said pusher when anoversized slug jams against said metering plate, and means for shuttingoff said power means after said power means has been mechanicallydisengaged from said pusher.

e. In a slug feeding device including a heating unit having a passagewaytherethrough, a rod arranged to move slugs through said passageway and arotatable disc to which said rod is eccentrically connected, apower-driven disc rotatable on the same axis as said rotatable disc, thepowerdriven disc having an opening therethrough, the first-mentioneddisc having a recess therein, a pin disposed in said opening and havinga beveled end portion engageable in said recess, spring means urgingsaid pm into a iirst position in which the beveled end portion isdisposed in said recess so that the discs are in driving relation, saidpin being movable in an axial direction to a second position in whichsaid discs are decoupled by obstruction of the movement of the 6first-mentioned rotatable disc, a switch forcone trolling thepower-driven disc, and an operating arm on said switch disposed in thepath of movement of said arm in its second position.

5. 1n a slug feeding device, a unit having an open ended generallyhorizontal passageway therethrough, l. eans for heating slugs in saidpassageway, an inclined ramp adjacent one end of said passageway andhaving a lower trough portion aligned with said passageway, areciprocable plunger aligned with said passageway and said troughportion, means for operating said plunger, mechanism for Varying the endof stroke of said plunger relative to said one open end of saidpassageway for determining the position of slugs adjacent the other openend of said passageway prior to ejection therefrom to maintain theentire lengths of the slugs in the passageway until the leading slug isdischarged from said other end, a metering plate adjacent said one endof said passageway and having an aperture smaller than the smallestcross-section of said passageway to prevent jamming of slugs therein,and load responsive mechanism to stop the means for operating theplunger upon jamming of a slug in said aperture.

6. In a slug feeding device, a unit having an open-ended generallyhorizontal passageway therethrough, means for heating slugs in saidpassageway, an incline` ramp adjacent one end or" said passageway andhaving a lower trough portion aligned with said passageway, areciprecahle plunger aligned with said passageway and said troughportion, means for operating said plunger and adjustable for Varying theend of stroke of said plunger relative to said one end of said'passageway and for determining the position of slugs adjacent the otherend of said passageway prior to ejection therefrom, and a metering plateadjacent said one end of said passageway and having an aperture smallerthan the smallest cross-section of said passageway to prevent jamming ofslugs therein, said plunger operating means including a clutch operativeto disengaged position upon a predetermined transmitted force to preventdamage to the device.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,075,891 Ayars Oct. 14, 1913 1,125,105 Insley Jan. 19, 19151,252,561 Fassinger Jan. 8, 1913 1,412,444 Baker et al. Apr. 11, 19221,563,365 Hollup Dec. 1, 1925 1,583,889 Lariviere May 11, 1926 1,799,106LaXo Mar. 3l, 1931 1,913,665 Frink June 13, 1933 1,986,802 Friedemann'Jan. 8, 1935 2,078,905 Fearnside Apr. 27, 1937 2,256,781 Nelson Sept.23, 1941 2,325,638 Strickland Aug. 3, 1948 2,556,234 Strickland, Jr June12, 1951 2,563,883 Strickland, Jr Aug. 14, 1951 2,572,073 Striokland, JrOct. 23, i 2,578,760 Strickland, Jr Dec. 18, 1351 2,604,577 Strickland,Jr., et al. July 22, 1952 2,644,075 Corteggiano et al. June 30, 1953

